Name: MSA-2
Brand: Selleck Chemicals
SKU: S9681
Rating: 5 (1 reviews)

MSA-2 is an orally available non-nucleotide human STING agonist with antitumor activity.

MSA-2 Chemical Structure

CAS: 129425-81-6

Selleck's MSA-2 has been cited by 1 publication

Purity & Quality Control

Batch: Purity: 99.96%

99.96

MSA-2 Related Products

Choose Selective STING Inhibitors

Biological Activity

Description

MSA-2 is an orally available non-nucleotide human STING agonist with antitumor activity.

Targets

STING ^[1]

In vitro
In vitro	MSA-2 in solution exists as monomers and noncovalent dimers in an equilibrium that strongly favors monomers; MSA-2 monomers cannot bind STING, whereas the noncovalent MSA-2 dimers bind STING with nanomolar affinity. MSA-2 exhibits substantially higher cellular potency in an acidified tumor microenvironment than normal tissue, owing to increased cellular entry and retention combined with the inherently steep MSA-2 concentration dependence of STING occupancy.^[1]
Cell Research	Cell lines	THP-1 cells, mouse macrophages
	Concentrations	20 μM, 0.16 μM-100 μM
	Incubation Time	5 h
	Method	In the primary screen, THP-1 cells are incubated, in 1536-well plates, with test compounds (20 μM) in a RPMI1640-based assay medium in the presence of 5% carbon dioxide at 37°C for 5 hours. IFN-b levels are determined using an AlphaLISA assay and an EnVision Reader and expressed as percentages of IFN-b induced by cGAMP. STING binding activity of compounds is evaluated with a competitive radioligand binding assay using tritiated cGAMP and membrane embedded full-length recombinant human and mouse STING generated in insect cells. STING pathway activation by MSA-2 is assessed by Western blotting, probing phosphorylation status and total protein levels of STING, TBK-1, and IRF3 by using commercially available antibodies.

In Vivo
In vivo	MSA-2 is orally available, manifesting similar oral and subcutaneous exposure in mice. In tumor-bearing mice, MSA-2 induced elevations of interferon-b in plasma and tumors by both routes of administration. Well-tolerated regimens of MSA-2 induced tumor regressions in mice bearing MC38 syngeneic tumors. In tumor models that are moderately or poorly responsive to PD-1 blockade, combinations of MSA-2 and anti-PD-1 antibody are superior in inhibiting tumor growth and prolonging survival over monotherapy.^[1]
Animal Research	Animal Models	C57BL/6J mice, NSG mice, BALB/c mice, nude NCr mice
	Dosages	25 mg/kg, 40 mg/kg, 50 mg/kg, 60 mg/kg, 80 mg/kg, 160 mg/kg
	Administration	intra tumor injection, SC, PO

References

[1] Bo-Sheng Pan, et al. Science. 2020 Aug 21;369(6506):eaba6098.

Chemical Information & Solubility

Molecular Weight	294.32	Formula	C₁₄H₁₄O₅S
CAS No.	129425-81-6	SDF	--
Smiles	COC1=C(OC)C=C2C=C(SC2=C1)C(=O)CCC(O)=O
Storage (From the date of receipt)	3 years -20°C powder	Storage of Stock Solutions Aliquot the stock solutions to avoid repeated freeze-thaw cycles	1 year-80°Cin solvent
Storage (From the date of receipt)	3 years -20°C powder		1 month-20°Cin solvent

In vitro
Batch:

DMSO : 59 mg/mL ( (200.46 mM)； Moisture-absorbing DMSO reduces solubility. Please use fresh DMSO.)

Ethanol : 5 mg/mL

Water : Insoluble

Molecular Weight Calculator

In vivo Batch: Add solvents to the product individually and in order.					In vivo Formulation Calculator
	Clear solution	5%DMSO 1 40%PEG300 2 5%Tween80 3 50%ddH2O	1.75mg/ml (5.95mM)	Taking the 1 mL working solution as an example, add 50 μL of 35 mg/ml clarified DMSO stock solution to 400 μL of PEG300, mix evenly to clarify it; add 50 μL of Tween80 to the above system, mix evenly to clarify it; then continue to add 500 μL of ddH2O to adjust the volume to 1 mL. The mixed solution should be used immediately for optimal results.	In vivo Formulation Calculator
Clear solution	5% DMSO 1 95% Corn oil	0.5mg/ml (1.70mM)	Taking the 1 mL working solution as an example, add 50 μL of 10 mg/ml clear DMSO stock solution to 950 μL of corn oil and mix evenly. The mixed solution should be used immediately for optimal results.
Clear solution	5%DMSO 1 40%PEG300 2 5%Tween80 3 50%ddH2O	1.0mg/ml (3.40mM)	Taking the 1 mL working solution as an example, add 50 μL of 20 mg/ml clarified DMSO stock solution to 400 μL of PEG300, mix evenly to clarify it; add 50 μL of Tween80 to the above system, mix evenly to clarify; then continue to add 500 μL of ddH2O to adjust the volume to 1 mL. The mixed solution should be used immediately for optimal results.

Preparing Stock Solutions

Molarity Calculator

Dilution Calculator Molecular Weight Calculator

In vivo Formulation Calculator (Clear solution)

Step 1: Enter information below (Recommended: An additional animal making an allowance for loss during the experiment)

Dosage: mg/kg Average weight of animals: g Dosing volume per animal:μL Number of animals:

Step 2: Enter the in vivo formulation (This is only the calculator, not formulation. Please contact us first if there is no in vivo formulation at the solubility Section.)

% DMSO + % + % Tween 80 + % ddH₂O

%DMSO+ %

Calculation results:

Working concentration: mg/ml;

Method for preparing DMSO master liquid: mg drug pre-dissolved in μL DMSO ( Master liquid concentration mg/mL, Please contact us first if the concentration exceeds the DMSO solubility of the batch of drug. )

Method for preparing in vivo formulation: Take μL DMSO master liquid, next addμL PEG300, mix and clarify, next addμL Tween 80, mix and clarify, next add μL ddH₂O, mix and clarify.

Method for preparing in vivo formulation: Take μL DMSO master liquid, next add μL Corn oil, mix and clarify.

Note: 1. Please make sure the liquid is clear before adding the next solvent.
2. Be sure to add the solvent(s) in order. You must ensure that the solution obtained, in the previous addition, is a clear solution before proceeding to add the next solvent. Physical methods such
as vortex, ultrasound or hot water bath can be used to aid dissolving.

Tech Support

Answers to questions you may have can be found in the inhibitor handling instructions. Topics include how to prepare stock solutions, how to store inhibitors, and issues that need special attention for cell-based assays and animal experiments.

Handling Instructions

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